The primary aim of this retrospective cohort study is to determine whether naturally and treatment-achieved pregnancies among infertility patients (infertile pregnancy cohort) are at higher risk for adverse outcomes as compared to naturally conceived pregnancies achieved by fertile women (fertile pregnancy cohort) and where these differences persist after controlling for maternal and infant factors such as maternal age, parity, and gestational age. The infertile pregnancy cohort (n=5160) will be comprised of 3 groups of women: (1) infertile women who conceived between 1/1/94-1/1/97 as a result of infertility treatments; (2) fertile women who conceived as a result of infertility treatment undertaken as a result of male factor infertility; and (3) infertile women who conceived naturally after presenting for infertility treatment. The fertile pregnancy cohort (n=5160) is the non-exposed comparison group composed of women frequency matched on date of conception and maternal age who do not have a history of infertility and who conceived naturally. The outcomes of interest include pregnancy complications (e.g., IUGR, placental complications, and pre-eclampsia), labor and delivery complications (e.g., operative delivery and still birth), neonatal complications (e.g., death, cerebral palsy, and mental retardation). We expect to have over 90% power to detect statistically significant differences been the infertile and fertile pregnancy cohorts in nearly all of these outcomes. Infertility, prenatal, L&D, and pediatric medical records will be reviewed and a maternal interview conducted to gather complete information on infertility and reproductive history, health status and outcomes, and care providers. The relationships will be analyzed using path analysis, considering differences in risk according to fertility status, infertility etiology, infertility treatments received, and other maternal characteristics.